What happened
On September 7, 2025, a CubCrafters Carbon Cub EX, registration N40DT, was involved in an accident near Thompsonville, Michigan. The flight departed from Thompsonville Airport (7Y2) at approximately 0917 EDT for a local flight under visual meteorological conditions.
Shortly after departure, the pilot observed a flicker on the Garmin G3X Touch display. Although no low voltage warning was initially issued, the engine monitoring display indicated the alternator was not charging, with the voltage reading 12.8 VDC. The pilot initiated a climbing turn to return to 7Y2. During the return flight, the pilot attempted to restore the alternator by cycling the field and main alternator circuit breakers, but the issue persisted. The pilot also noted the backup ignition battery was at 12.8 VDC.
To preserve the backup ignition battery, the pilot continued the flight using the main battery. While on final approach to 7Y2, a low voltage warning appeared on the Garmin G3X Touch display. The pilot switched to the backup ignition battery, but observed the voltage drop rapidly from 12.8 VDC to 0 VDC, resulting in a total loss of engine power. The pilot identified that the backup battery was faulty, as it provided power for only one to two minutes.
At approximately 300 feet on short final, the pilot performed a forced landing into a wooded area. The aircraft came to rest nose-down in the trees, resulting in substantial damage to both wings and the wing struts. The pilot was not injured, while the passenger sustained minor injury.